Baggage and cargo container door mechanism

ABSTRACT

A door mechanism which forms an openable side of a cargo container. The door consists of upper and lower sections joined by a horizontal hinge. The doors are supported by means of brackets at the upper corners of the upper door sections which carry rollers running in tracks extending along the top of the container ends. Pins projecting from the lower edge of the lower door section engage suitable recesses in the container base when the doors are closed and a latch mechanism is provided for holding the door securely in its closed position.

United States Patent Sprick et al. 1 Dec. 19, 1972 [54] BAGGAGE ANDCARGO CONTAINER [56] 7 References Cited DOOR MECHANISM UNITED STATESPATENTS [721 mentors: Sp'ick; Frank Mmse 2,569,254 9/1951 Page .Q..220/3s x both of Akron; Alexander 3,672,529 6/l972 Feddersen ..220/3sxCuyahoga Falls; Oscar W. Meller; I I J0hn Lflvich, both of Akron,Primary Examiner-George T. Hall of Ohio Att0rneyJ. G. Pere et al.

[73] Assignee: Goodyear Aerospace Corporation, [57] a ABSTRACT I IAkron, Ohio' a r A door mechanism WhlCh forms anopenable side of aFiled; a 1971 cargo container. The door consists of upper and lower 9sections joined by a horizontal hinge. The doors are Appl' 192Asupported by means of brackets at the upper corners of the upper doorsections which carry rollers running [52] U.S.Cl .v220/38,220/1.5 intracks x nding along the "top of the container [51] Int Cl ..B65d 43/16ends- Pins Projecting from t r edge of the lower [58] Field 220/38 4]1.5 34; 49/197 door section engage suitablerecesses inthe containerbasewhen the doors are closed and a latch mechanism is provided forholding the door securely in its closed position a 17 Claims, 16 DrawingFigures PATENTED DEC 1 9 I972 SHEU 1 [IF 5 INVENTORS HOLZER LOVICHALEXANDER JOHN W. Y OSCAR N. HELLER FRANK C. MORSE WALTER F. SPRICKauaqraubv ATTORNEYS PAIENTEDBEI: 19 I972 SHEET 2 BF 5 FIG.2

FIG. 3

INVENTORS ALEXANDER HOLZER JOHN W.LOVICH OSCAR N. HELLER FRANK C. MORSEWLTER F. S RICK ATTOR EYS PATENTE D 19 I97? 3, 706, 392

sum 3 or s I/IIIIIIIIIIII/IIIIII/ Ill INVENTORS ALEXANDER HOLZER v JOHNW. LOVICH '4 BY OSCAR N. MELLER FRANK C. MORSE WALTE F. OYHCK 0% OlATTORNEYS PATENTED 3.706392 sum u or 5 FIG. l5

InwEn INVENTORS m in" ALEXANDER HOLZER JOHN w. LOVICH BY OSCAR ".MELLERFRANK c. MORSE WALTER F. SPRICK ATTORNEYS PATENTED an: 19 1912 SHEET 5BF 5 FIG. l2

FIG. I3

FIG IO WALTEZ SPRICK I ATTORNEYS BAGGAGE AND CARGO CONTAINER DOORMECHANISM The present invention relates to cargo containers and moreparticularly to an improved door construction for such containers.

Cargo containers are now widely used to facilitate the handling ofbaggage and other cargo. For example, many of the larger modern aircraftare designed to receive cargo containers. Difficulties have beenencountered, however, with the door mechanism of the containerspresently in use. Since there may only be a small area available inwhich the container is to be loaded or unloaded the door mechanism mustbe designed so that it can be opened and closed without being movedthrough a large area. Also, where conveyor systems are used to handlethe containers, the rails of the conveyor may present obstaclesrequiring the lower section of the door to be lifted upwardly before itcan be swung to an open position. The arrangements which had beenproposed heretofore to meet these requirements include doors which areformed of a number of sections each of which is guided by rollersrunning in tracks extending on the side of the opening and along theinner face of the top of the container. Such an arrangement, however,reduces the amount of available storage space within the container and,unless the rollers and tracks are closely fitted precision members, doesnot provide for tight sealing of the container. Another arrangementwhich has been used utilizes an elongated guide member which runs in atrack mounted on the door. This arrangement requires a heavy doorconstruction to provide sufficient rigidity for the track. Also, withsuch a construction the door must be opened carefully or jamming willoccur as one side of the door attempts to lead the other.

It is the primary object of the present invention to provide an improveddoor operating mechanism for a cargo container.

A further object of the present invention is the provision of a dooroperating mechanism in which the door may be of lightweight constructionwhile providing for the secure sealing ofthe container.

Another object of the present invention is the provision of a dooroperating mechanism for a cargo container in which the possibility ofjamming the door is substantially reduced.

Among the other objects of the invention are the provision of a dooroperating mechanism for a cargo container which mechanism does notoccupy any otherwise usable space within the container, the provision ofan operating mechanism which permits the door to be opened and closed ina relatively small area and which permits the opening and closing of thedoor even if there are obstructions present near the base of thecontainer, the provision of a container door assembly which will remainin its closed position even if the guide roller becomes damaged orbroken, and the provision of a door mechanism in which the operatingmembers are readily accessible for repair or replacement, if necessary.

The above and other objects of the invention which will become apparentin the following detailed description are achieved by providing a doormechanism for a cargo container which consists, essentially, of a doorhaving upper and lower sections connected by a horizontal hinge, rollersmounted to brackets at the upper corners of the upper door section,guidetracks extending lengthwise along the upper ends of the end panelsof the containers for receiving the rollers, anchoring pins at the lowerend of the door for engaging recesses in the container base when thedoor is closed, and a latching mechanism for holding the door securelyin a closed position.

For a more complete understanding of the invention and the objects andadvantages thereof reference should be had to the following detaileddescription and the accompanying drawings wherein there is shown apreferred embodiment of the invention.

In the drawing:

FIG. 1 is a perspective view of a cargo container hav ing the doormechanism of the present invention;

FIG. 2 is a side elevational view of the cargo container of FIG. 1;

FIG. 3 is an end elevational view of the cargo container;

FIG. 4 is a fragmentary vertical sectional view taken along the line 4-4of FIG. 2',

FIGS. 5, 6, and 7 are fragmentary vertical sectional views taken alongthe lines 55, 66, and 77, respectively, of FIG. 3;

FIG. 8 is a fragmentary vertical sectional view taken along the line 88of FIG. 2;

FIG. 9 is a fragmentary horizontal sectional view taken along the line99 of FIG. 3 and showing the door latch mechanism employed on thecontainer of FIG. 1;

FIG. 10 is a fragmentary sectional view taken along the line l010 ofFIG. 3;

FIG. 11 is a fragmentary elevational view of the center portion of thedoor guide track;

FIG. 12 is a fragmentary elevational view showing the relationship ofthe guide roller and support bracket to the door and the track;

FIG. 13 is a fragmentary sectional view taken along the line 1313 ofFIG. 12;

FIG. 14 is a schematic cross-sectional view showing the door in apartially opened position;

FIG. 15 is a view similar to that of FIG. but showing the door in itsfully opened position; and

FIG. 16 is a fragmentary sectional view taken along the line 16-16 ofFIG. 3.

CONSTRUCTION OF THE CONTAINER A cargo container having the doormechanisms of the present invention is illustrated-in FIGS. 1-3 anddesignated generally by the reference numeral 10. This container has abase 12, end panels 14 which may be corrugated metal sheeting, a toppanel 16, and side panels 18. The side panels 18 are doors which may beopened to provide access to the container. As will be discussed in moredetail below, each of the doors 18 consists of a lower door section 20and an upper section 22 which are joined together by a horizontal hinge24. Brackets 26 are affixed to the upper corners of the upper doorpanels 22 and these brackets journal rollers which run in tracks 28extending across the top of the side panels 14. The lower edge of thedoor panel is provided with a number of pins 30which engage matingopenings 32 in the base 12 when the door is in a closed position. Alatch mechanism 34 is provided for fastenl060ll 0598 ing the door in itsclosed position. The cargo container may be provided with shelves 36, ifdesired, and these shelves may be removably secured within the.container. Handles 38 may be provided on the ends of the container tofacilitatemovement and additional handles 40 provided on the door panels18.

It should be understood that the present invention resides in theconstruction of the door assembly and operating mechanism and that thecontainer may be of other configurations than that shown. The base andtop panels 12 and 16, respectively, may be of any suitable construction.Likewise, the side panels 14 may be of any suitable construction and arenot necessarily formed of corrugated sheets, as illustrated. Preferably,the side panels 14 are removably connected to the base 12 and top panel16 so that the container may be disassembled for shipment or storage.One possible arrangement for securing the side panels 14 tothe base 12is shown in FIG. 4 where the lower end of panel 14 is provided with arail 94 which is riveted to the panel and which includes an inwardlyprojecting web 96 which may be secured to the base by screws 98.

I DOOR CONSTRUCTION As can be seen from FIGS. 5 and 6, the upper doorpanel 22 consists of acorrugated metal sheet 38 positioned with thecorrugation extending vertically. A top rail 40 having downwardlyprojecting flanges 42 and 44 is secured to the upper edge of thecorrugated sheet 38 by means of rivets 46 and 48. The rail 40, which ispreferably an aluminum extrusion, has aweb portion projecting at rightangles to the plane of the corrugated sheet 38 and terminating in a lip52 extending generally parallel to the sheet 38. The rail 54 which formsthe front edge of the top panel 16 has a continuous groove 60 whichmates with the lip 52 of the door top rail 40. This arrangement providesa seal between the door and top member when the door is closed, and, aswill be discussed below, holds the door in a closed position if theroller assemblies 26 become broken or damaged. A sealing gasket (notshown) may also be provided to form a tight seal between the rails 40and 54. The rail 54 has projecting flanges 58 and 60 for engaging thetop panel 16 and may be secured to this panel by any suitable means,such as riveting or welding.

A beam 60 extends along the lower edge of the corrugated sheet 38, thebeam having upwardly projecting flanges 64 and 66 for engaging oppositefaces of the corrugated sheet 38 and rivets 66 are employed to securethe beam to the sheet 38. A suitable handle 68 may be attached to thebeam, preferably midway between the edges of the'door panel 18. The beam60 is preferably a hollow aluminum extrusion forming a box beam whichextends the width of the door assembly. This construction permits theuse of relatively light gauge corrugated sheeting 38 while stillmaintaining sufficient strength and rigidity in the door assembly.Further, the use of a horizontally extending beam in conjunction withthe vertically extending corrugations of the sheets provides anexceptionally rigid yet lightweight door assembly. It should be noted,however, that while this is the preferred construction, other materialsmay be used in place of the corrugated sheeting 38 or the sheeting maybe arranged with the corrugations extending horizontally.

The lower door section 20 also consists of a corrugated sheet 70 whichagain, preferably, has its corrugations extending vertically. An upperrail 72 having parallel flanges 74 is riveted to the upper edge of thecorrugated sheet 76 and extendsthe width of the door assembly. This rail72, again preferably an aluminum extrusion, has a web portion 78extending upwardly from the rail 72 and at an angle to the plane of thecorrugated sheet 70. Preferably, this angle is approximately 45. Oneleaf of the hinge 24 is riveted or otherwise connected to the bottomsurface of the beam 60 while the other leaf of the hinge 24 is rivetedor otherwise connected to the angled web 78 of the rail 72..The

hinge 24 may be a stainless steel piano hinge. However,

or neoprene gasket, is provided along the lower surface of the bottomrail 80 performing a weathertight seal with the container base 12 whenthe door is closed. The pins 30 are connected to the lower rail 80 bysuitable fasteners such as bolts 88.

The lateral edges of the upper door panel 22 maybe provided with siderails 90. Side rails 92 may also be provided on the lateral edges 'ofthe lower door panel 20. Preferably, each of these rails and 92 carriesa sealing gasket for engaging the face of the rail which forms thelateral edge of the container side panel 14. Obviously, if desired, thesealing strip may be affixed to the side panel rail 100 and engage theinner face of the door edge rails 90 and 92.

DOOR OPERATING MECHANISM Referring now to FIGS. 8, 12, and 13, the doorguide roller assemblies 26 and the tracks 28 will now be described.Affixed to each of the upper corners of the door panel assembly 18 areroller guide assemblies 26. Each assembly has an angle bracket 101 whichhas a first leg 102 extending parallel to the plane of the corrugatedsheets forming the door and which is securely riveted or bolted to thedoor and a second leg 104 extending at right angles to the plane of thedoor. A stud or other suitable pin 106 is provided at the outer end ofthe bracket leg 104 and a guide roller 108 is joumaled on the stud orpin. The roller 108 is preferably a nylon roller and, as can be seenfrom FIG. 13, the edge 110 of the roller furthest from the bracket isrounded on a fairly large radius while the edge 112 of the roller closerto the bracket has a smaller radius. A suitable bushing 116 may beprovided on the stud 106 to assure free rotation of the roller 108.

The track 28 in which the roller 108 runs forms the top rail of the endpanel 14 of the container assembly. As will be seen from FIG. 8, thetrack-28 has a channellike passage 116 extending its length and theroller 108 runs in this passage, generally bearing on the wall 118. Adownwardly projecting lip 120 serves to retain the roller within thechannel 116. It should be noted that the roller 108 has a loose fittingrelationship with the inset l 0599 channel 116, the roller being ofsufficient heighth to be retained in place by the downwardly projectinglip 120 but normally being free to move a limited extent both verticallyand laterally within the confines of the channel 116. This arrangementeliminates one of the major difficulties encountered with priorcontainer door mechanisms where the door guide assemblies haverelatively close tolerances. In such situations, if one side of the dooris moved further than the opposite side, that is, if one side is leadingthe other side, the guide members tend to jam against the sides of theguiding track and the door becomes wedged. In the system of the presentinvention, however, the rollers 108 will continue to move within thechannel 116 of the track 28 even if the door is considerably skewed. Theradiused corners 110 and 112 of the roller together with the loosetolerances maintained between the roller and the walls of the channel116 facilitate this action.

At the midpoint of the track 28 there is provided a stop member 124which is retained by a bolt 126. The bolt 126 also retains a spring 128which has downwardly projecting end portions 130 protruding into thechannel 116 through suitable notches 132 in the rail 128. The downwardlyprojecting end portion 130 of the spring 128 serve to engage the rollers108 to retain the doors in their fully opened position. In the containerconstruction illustrated, the rollers for the doors on opposite sides ofthe container travel to substantially the midpoint of the container sothat a common stop member 124 may be employed. Obviously, in a containerconstruction in which the depth of the container is relatively greaterthan the heighth, separate stop members will be provided for the doorson the front and rear sides of the container.

The latch mechanism 34 employed to hold the doors in a closed positionmay be any suitable latch. Also, the location of the latch mechanismsare not critical so long as the mechanisms are capable of holding thedoor securely in its closed position. One mechanism which may be used isillustrated in FIG. 9. This latch mechanism has a housing 124 which ismounted at the end 126 of the beam 60, the outer wall of the beam beingcut away at the end thereof. A latching stud 128 which has afrusto-conical head portion 130 and an annular groove 132 immediatelybelow the head portion 130 is secured to the end panel rail 100 in anysuitable manner. Slidably received within the housing 124 is a latchplate 134 which has a notch 136 at one end. When the latch plate is inthe position shown in solid outline in FIG. 9 the notch 136 engages theannular groove 132 of the stud 128 to securely lock the door assemblyand end panel 14 together. When the latch plate is slid to its openposition, as shown in dotted outline in FIG. 9, the end portion of thelatch plate is moved clear of the stud 130 so that the door may beopened. This latch mechanism is described in greater detail in PatentApplication Ser. No. l,590, filed Oct. 27, l97l for Container DoorLatch.

The manner in which the door assembly 18 is opened is illustrated inFIGS. 14 and 15. When the latch assemblies 34 have been released, thedoor is opened by pulling the handle 68 outwardly. This will result in apivoting of the upper door section 22 about the studs .106 while thelower door assembly 20 pivots inwardly about the hinge 24 so that thelower end of the door moves substantially vertically. This pivoting ofthe lower door section 20 relative to the upper door section 22 in thedirection of the arrow A causes the lowermost end of the door to beraised before being swung outwardly and thus permits the door to clearobstructions such as the rail 138. It will be noted that the amount ofmovement in the direction of the arrow A is limited by the bottom sideof the beam and the web 78 of the lower door top rail 72. Typically,this movement will be through an angle of less than 45. Once the doorhas been raised to the position shown in FIG. 14, the lower door section20 can be pivoted upwardly about the hinge 24 in the direction of thearrow B to bring this door section into substantially parallelrelationship with the upper door section 22. The top rail 40 of theupper door section 22 is provided with suitable clips 134 which engagethe pins 30 to hold the upper section in this folded position. The doormay now be continued to be moved upwardly, pivoting about the axis ofthe roller 108. As the door moves upwardly the roller 108 is free tomove forwardly in the track 28, that is in the directions of the arrowC. This forward motion of the roller brings the upper portion of thedoor 22 to a position clear of the rail 54 at the edge of the top panel16. The door is moved upwardly until it has assumed a substantiallyhorizontal position. The door assembly 18 is now moved towards thecontainer centerline, the rollers 108 running in the tracks 28 untilthey contact the stop members 124. Wear plates 122 may be provided atthe corners of the top panel 16 so that the door can be easily slid toits fully opened position. Preferably, these plates 122 are formed ofnylon or other suitable material which will not mar the faces of thedoor sections 20 and 22. lt should be noted that as the door is openedonly a small amount of distance above the container is necessary, thedoor being in a fully folded position before being slid along the topsurface of the container. This arrangement, it will be noted, requiresonly a limited amount of vertical clearance above the container.

In order to hold the door in its open position hold down straps 138 maybe provided. As is shown in FIG. 16, the straps 138 may be connected toa suitable rod 140 riveted to the corrugated sheet forming the lowerdoor panel. A book member 142 is provided at the free end of the strap138 and a rod 144 may be provided on the corrugated sheet 70 forretaining this hook when the strap is not in use. The hook 140 engagesthe lip portion of the track 128 when the door is open to provide a holddown, preventing the door from accidentally being blown or knocked fromits fully opened position.

As can be seen clearly from FIGS. 5 and 12, when the door is in itsclosed position, the lip 52 of the door top rail 40 engages the groove60 of the top panel edge rail 54. Should one of the roller supportbrackets 101 become broken or one of the rollers 108 disengaged from thetrack 28 while the door is closed, the interlocking relationship of thelip 52 and groove 60 will hold the upper edge of the door in its closedposition.

It should also be noted that the bracket 101 and rollers 108 are readilyaccessable and may be removed for repair or replacement, if necessary,without requiring the disassembly of the door itself.

l060ll 0600 While only the best known embodiments of the invention havebeen illustrated and described in detail herein, it will be clearlyunderstood that the invention is not limited thereto or thereby.Reference should therefore be had to the appended claims in determiningthe true'scope of the invention.

What is claimed is:

l. A door assembly for a container having a top panel, a base panel, anda pair of end panels connecting the top and base panels along oppositeedges, compris- 'ing:

a door panel on at least one side of the container;

a pair of guide rails, one rail extending horizontally along the upperedge of each endpanel;

a pair of guide rollers, one roller being associated with and running oneach guide rail; and

a pair of brackets, one bracket being secured to each of the uppercorners of the door panel, extending perpendicular to the plane of thedoor panel, and journaling one of the guide rollers for rotation about ahorizontal axis parallel to the plane of the door panel. *2. The doorassembly according to claim 1 wherein the door panel is comprised ofupper and lower sections and a horizontally extending hinge connectingthe upper and lower sections.

3. The door assembly according to claim 2 wherein the hinge permits thelower section to pivot relative to the upper section through only anangle of less than 45 toward the container and an angle of approximately180 away from the container.

4. The door assembly according to claim 1 further including means tosecure the lower end of the door panel to the base panel when the doorpanel is in its closed position.

5. The door assembly according to claim 1 further including latch meansto secure the door in its closed position.

6. The door assembly according to claim I wherein each guide rail is ofchannel-like configuration having its open side directed away from thecontainer.

7. A container door assembly for a container having top, bottom, and endwalls and at least one open side, comprising:

a door panel which, when in closed position, covers the open side of thecontainer;

latching means for securing the door panel in closed position; and

a guide mechanism for the door panel to direct the panel between itsclosed position and an open position in which the panel is positionedabove and substantially parallel to the top of the container,

the mechanism comprising a pair of channel-like tracks, the tracks beinglocated at opposite edges of the top wall of the the ganel. 8. The cntamer door assembly according to claim 7 wherein the door panel iscomprised of upper and lower panel sections and hinge means connectingthe upper and lower sections.

9. The container door assembly according to claim 8 wherein the latchingmeans comprises at least'one pin projecting downwardly from the loweredge of the lower panel section, the bottom wall'of the container havinga recess for receiving the pin, a first latching member mounted on thedoor panel, and a second latching member mounted on the container, thefirst and second latching members co-operating to releasably secure thedoor panel. v

10. The container door assembly according to claim 9 further includingclip means carried by the upper panel section for engaging the pin toretain the lower panel section in folded relation to the upper panelsection.

11. The container door assembly according to claim 7 wherein each trackcomprises a rail connecting the top wall to the respective side wall ofthe container.

12. The container door assembly according to claim 11 wherein the rollerreceiving portion of each track is of generally rectangular crosssection having a slot extending along the outer side edge of the track.

13. The container door assembly according to claim 12 wherein each guideroller is a cylindrical roller of lesser diameter and width thantheheighth and width, respectively, of the channel, the edges of the rollerbeing rounded.

14. The container door assembly according to claim 13 wherein the radiusof the roller edge adjacent the outer side of the channel is smallerthan the radiusof the opposite edge of the roller.

15. The container door assembly according to claim 11 wherein thechannel portion of each track is offset inwardly from the plane of thecorresponding end wall of the container.

16. The container door assembly according to claim 7 further including astop within each track for limiting inward movement of the rollers.

17. The container door assembly according to claim 16 further includingmeans adjacent each stop for releasably engaging the roller to hold thedoor panel in its fully open position.

1. A door assembly for a container having a top panel, a base panel, anda pair of end panels connecting the top and base panels along oppositeedges, comprising: a door panel on at least one side of the container; apair of guide rails, one rail extending horizontally along the upperedge of each end panel; a pair of guide rollers, one roller beingassociated with and running on each guide rail; and a pair of brackets,one bracket being secured to each of the upper corners of the doorpanel, extending perpendicular to the plane of the door panel, andjournaling one of the guide rollers for rotation about a horizontal axisparallel to the plane of the door panel.
 2. The door assembly accordingto claim 1 wherein the door panel is comprised of upper and lowersections and a horizontally extending hinge connecting the upper andlower sections.
 3. The door assembly according to claim 2 wherein thehinge permits the lower section to pivot relative to the upper sectionthrough only an angle of less than 45* toward the container and an angleof approximately 180* away from the container.
 4. The door assemblyaccording to claim 1 further including means to secure the lower end ofthe door panel to the base panel when the door panel is in its closedposition.
 5. The door assembly according to claim 1 further includinglatch means to secure the door in its closed position.
 6. The doorassembly according to claim 1 wherein each guide rail is of channel-likeconfiguration having its open side directed away from the container. 7.A container door assembly for a container having top, bottom, and endwalls and at least one open side, comprising: a door panel which, whenin closed position, covers the open side of the container; latchingmeans for securing the door panel in closed position; and a guidemechanism for the door panel to direct the panel between its closedposition and an open position in which the panel is positioned above andsubstantially parallel to the top of the container, the mechanismcomprising a pair of channel-like tracks, the tracks being located atopposite edges of the top wall of the container and extendingperpendicular to the plane of the open side, a guide roller associatedwith each track and running in the channel thereof, and a bracketjournaling each roller for rotation about an axis parallel to the planesof the opening and the top wall, the brackets being secured to therespective upper corners of the panel and extending generallyperpendicular to the plane of the panel.
 8. The container door assemblyaccording to claim 7 wherein the door panel is comprised of upper andlower panel sections and hinge means connecting the upper and lowersections.
 9. The container door assembly according to claim 8 whereinthe latching means comprises at least one pin projecting downwardly fromthe lower edge of the lower panel section, the bottom wall of thecontainer having a recess for receiving the pin, a first latching membermounted on the door panel, and a second latching member mounted on thecontainer, the first and second latching members co-operating toreleasably secure the door panel.
 10. The container door assemblyaccording to claim 9 further including clip means carried by the upperpanel section for engaging the pin to retain the lower panel section infolded relation to the upper panel section.
 11. The container doorassembly according to claim 7 wherein each track comprises a railconnecting the top wall to the respective side wall of the container.12. The container door assembly according to claim 11 wherein the rollerreceiving portion of each track is of generally rectangular crosssection having a slot extending along the outer side edge of the track.13. The container door assembly according to claim 12 wherein each guideroller is a cylindrical roller of lesser diameter and width than theheighth and width, respectively, of the channel, the edges of the rollerbeing rounded.
 14. The container door assembly according to claim 13wherein the radius of the roller edge adjacent the outer side of thechannel is smaller than the radius of the opposite edge of the roller.15. The container door assembly according to claim 11 wherein thechannel portion of each track is offset inwardly from the plane of thecorresponding end wall of the container.
 16. The container door assemblyaccording to claim 7 further including a stop within each track forlimiting inward movement of the rollers.
 17. The container door assemblyaccording to claim 16 further including means adjacent each stop forreleasably engaging the roller to hold the door panel in its fully openposition.